7-(D-a-hydroxy-2-arylacetamido)-3-(3-hydroxypyridazin-6-ylthiomethyl)-3-cephem-4-carboxylic acids

ABSTRACT

7-(D- Alpha -Hydroxy-2-arylacetamido)-3-(3-hydroxy-pyridazine-6ylthiomethyl)-3-cephem-4 -carboxylic acids and their nontoxic, pharmaceutically acceptable salts are valuable as antibacterial agents and are particularly valuable as therapeutic agents in poultry and animals, including man, in the treatment of infectious diseases caused by many Gram-positive and Gramnegative bacteria.

United States Patent Naito et al.

Oct. 7, 1975 7-(D-a-HYDROXY-Z-ARYLACETAMlDO)-3- (3-HYDROXYPYRlDAZlN-6- YLTHIOMETHYL)-3-CEPHEM-4- CARBOXYLIC ACIDS Inventors: Takayuki Naito, Tokyo; Jun

Okumura; Hajime Kamachi, both of Yokohama, all of Japan Assignee: Bristol-Myers Company, New York,

Filed: May 24, 1974 Appl. No.: 473,021

U.S. Cl. 260/243 C; 424/246 lnt. Cl. C07D 501/24 Field of Search 260/243 C [56] References Cited UNITED STATES PATENTS 3,855.2!3 l2/l974 Dunn et al. 260/243 C Primary Examiner-Nicholas S. Rizzo Attorney, Agent, or Firm Herbert W. Taylor. Jr.

[57] ABSTRACT 54 Claims, N0 Drawings 1 7-(D-a-HYDROXY-2-ARYLACETAMIDO)-3-(3- I-IYDROXYPYRIDAZIN-6-YLTHIO1VIETIIYL )-3- CEPI-IEM- -l-CARBOXYLIC ACIDS BACKGROUND OF THE INVENTION 1. Field of the Invention The cephalosporins of the present invention possess the usual attributes of such compounds and are particularly useful in the treatment of bacterial infections by parenteral administration.

2. Description of the Prior Art The cephalosporins are a well-known group of semisynthetic anti-bacterial agents made originally, for example, by acylation of the 7-amino group of the nucleus 7-aminocephalosporanic acid (7-ACA) and later by similar acylation of nuclei derived therefrom, as by modification of its substituent at the 3-position. Various reviews have appeared in the scientific literature (e.g. Cephalosporins and Penicillins Chemistry and Biology, edited by Edwin H. Flynn, Academic Press, New York, 1972, and particularly pages 554-569) and in the patent literature, e.g. as in U.S. Pat. Nos. 3,687,948, 3,741,965, 3,759,904, 3,759,905, 3,766,175 and 3,776,906 (all U.S. CLass 260-243C). Issued patents on 3-thiolated cephalosporins in which the 7-substituent is a. a-Amino-oz-phenylacetamido include U.S. Pat. Nos. 3,641,021, 3,734,907, 3,687,948, 3,741,965, 3,757,015, 3,743,644, Japan Pat. No. 71/24400 (Farmdoc 463745), Belgium Pat. No. 776,222 (Farmdoc 38983T; U.K. Pat. No. 1,328,340 which includes various substituents on the benzene ring), Belgium Pat. No. 772,592 (Farmdoc 19696T; U.S. Pat. Nos. 3,687,948, 3,734,907 and 3,757,012), West Germany Pat. No. 2,202,274 (Farmdoc 504281) corresponding to U.S. Pat No. 3,759,904, Netherlands Pat. No. 7205644 (Farmdoc 76309T; U.S. Pat. No. 3,757,014); and

b. mor p-aminoethoxyphenylacetamido as Netherlands Pat. No. 72/13968 (Farmdoc 2474OU) corresponding to U.S. Pat. No. 3,759,905 and c. o-aminomethylphenylacetamido Netherlands Pat. No. 72/06326 (Farmdoc 76374T) (which also reviews the older patent literature concerning substituted 7-phenylacetamidocephalosporanic acids) corresponding to US. Pat. No. 3,766,176 and 3,766,175; and d. N-(phenylacetimidoyl)aminoacetamido as U.S.

Pat. No. 3,692,779; and

e. a-amino-a-(1,4-cyclohexadienyl)acetamido as in Belgium Pat. No. 776,222 (Farmdoc 38983T; U.K. Pat. No. 1,328,340).

Additional similar disclosures are found in U.S. Pat. No. 3,692,779 (Belgium Pat. No. 771,189; Farmdoc 12819T), Japan Pat. No. 72/05550 (Farmdoc I2921T), Japan Pat. No. 72/0555] (Farmdoc 12922T), U.S. Pat. No. 3,719,673 (Belgium Pat. No.

759,570; Farmdoc 39819S), Belgium Pat. No. 793,31 1 (Farmdoc 39702U) and Belgium Pat. No. 793,191 (Farmdoc 39684U).

Issued disclosures of 3-thiolated cephalosporins in which the 7-substituent is 7-mandelamido (7-ahydroxyphenylacetamido) are found, for example, in U.S. Pat. No. 3,641,021, France Pat. No. 73.10112, U.S. Pat. No. 3,796,801, Great Britain Pat. No. 1,328,340 (Farmdoc 389831), U.S. Pat. No. 3,701,775, Japan Pat. No. 4844293 (Farmdoc 55334U) and in Hoover et al., J. Med. Chem. 17(1), 34-41 (1974) and Wick et al., Antimicrobial Ag. Chemo, 1(3), 221-234 (1972).

SUMMARY OF THE INVENTION This invention comprises the acids having the D configuration in the 7-sidechain and the formula wherein R is and Y is hydrogen, chlorine, bromine, fluorine, trifluoromethyl, amino, nitro, hydroxy, lower-alkyl of 1-4 carbon atoms or lower alkoxy of l-4 carbon atoms and the nontoxic, pharmaceutically acceptable salts of those acids and the easily hydrolyzed esters of those acids including especially the pivaloyloxymethyl, acetoxymethyl, acetonyl, phenacyl and methoxymethyl esters and the silyl esters such as the trimethylsilyl ester.

In the preferred embodiments of this invention R is 2-thienyl, 3-thienyl, phenyl, chlorophenyl, bromophenyl, trifluoromethylphenyl, tolyl or methoxyphenyl.

Such salts include the nontoxic carboxylic acid salts thereof, including nontoxic metallic salts such as sodium, potassium, calcium and aluminum, the ammonium salt and substituted ammonium salts, e.g. salts of such nontoxic amines as trialkylamines including triethylamine, procaine, dibenzylamine, N-benzyl-betaphenethylamine, l-ephenamine, N,N dibenzylethylenediamine, dehydroabietylamine, N,N- bis-dehydroabietylethylenediamine, N-(lower)-alkylpiperidine, e.g. N-ethylpiperidine, and other amines which have been used to form salts with benzylpenicillin.

A particularly preferred embodiment of this invention comprises the acid having the D configuration in the 7-sidechain and the formula wherein R is as defined above and the nontoxic salts and easily hydrolyzed esters thereof which comprises reacting the compound of the formula or a salt or easily hydrolyzed ester or Schiff base (as with benzaldehyde) thereof with an acylating derivative of the acid (in which the hydroxy group may be protected) having the formula wherein R is as defined above and wherein B represents hydrogen or the protecting group (that is, with that acid or its reactive derivative substituted at the carboxyl group) to produce the compound (in which the hydroxyl group may be protected) having the formula if R- H- NH H H or the corresponding salt or easily hydrolyzed ester thereof wherein B represents hydrogen or the protecting group, and if such a protecting group is present subsequently subjecting the resulting compound to chemical removal of the protecting group, that is, subjecting the resulting compound to elimination reaction of the protecting group.

The compound of the present invention is prepared according to the present invention by coupling with a particular 3-thiolated-7-aminocephalosporanic acid designated 11, that is, 7-amino-3-(3-hydroxypyridazin- 6-ylthiomethy1)-3-cephem-4-carboxy1ic acid or a salt or easily hydrolyzed ester or Schiff base as with benzaldehyde thereof (including, but not limited to, those of US. Pat. No. 3,284,451 and U.K. Pat. No. 1,229,453 and any of the silyl esters described in US. Pat. No. 3,249,622 for use with 7-amino-penicil1anic acid and used in Great Britain Pat. No. 1,073,530 and particularly the pivaloyloxymethyl, acetoxymethyl, methoxymethyl, acetonyl, phenacyl, p-nitrobenzyl and B,B,fl-trich1oroethy1 esters) D-mandelic acid or a substituted D-mandelic acid as described herein or their functional equivalent as an acylating agent for a primary amino group. After coupling, any hydroxy blocking group present is removed to give the desired product.

Thus, with respect to said substituted or unsubstituted D-mandelic acid to be used to couple with compound ll, functional equivalents include the corresponding acid anhydrides, including mixed anhydrides and particularly the mixed anhydrides prepared from stronger acids such as the lower aliphatic monoesters of carbonic acid, or alkyl and aryl sulfonic acids and of more hindered acids such as diphenylacetic acid. A particularly useful anhydride is D-mandelic acid carboxyanhydride (US. Pat. No. 3,167,549) or the corresponding substituted D-mandelic acid carboxyanhydride. In addition, an acid azide or an active ester or thioester (e.g., with p-nitrophenyl, 2,4-dinitropheno1, thiophenol, thioacetic acid) may be used or the free acid itself may be coupled with compound 11 after first reacting said free acid with N,N'-dimethy1chloroformiminium chloride [cf, Great Britain Pat. No. 1,008,170 and Novak and Weichet, Experienn'a XXI, 6, 360 (1965)] or by the use of enzymes or of an N,N'- carbonyldiimidazole or an N,N'-carbony1ditriazole [cf. South African patent specification No. 63/2684] or a carbodiimide reagent [especially N,N'-dicyc1ohexylcarbodiimide, N,N'-diisopropylcarbodiimide or N- cyclohexy1-N'-( 2-morpho1inoethy1)carbodiimide; cf. Sheehan and Hess, J. Amer. Chem. Soc., 77, 1967 (1955) or of alkylylamine reagent [cf. R. Buijle and H. G. Viehe, Angew, Chem. International Edition 3, 582, (1964)] or of an isoxasolium salt reagent [cf. R. B. Woodward, R. A. Olofson and H. Mayer, J. Amer. Chem. Soc, 83, 1010 1961 )1, or of a Kietenimine reagent [cf. C. L. Stevens and M. F. Munk, J. Amer. Chem. Soc, 80, 4065 (1958)] or of hexachlorocyclotriphosphatriazine or hexabromocyclotriphosphatriazine (US. Pat. No. 3,651,050) or of diphenylphosphoryl azide [DPPA; J. Amer. Chem. $00., 94, 6203-6205 1972)] or of diethylphosphoryl cyanide [DEPC', Tetrahedron Letters No. 18, pp. 1595-1598 1973)] or of diphenyl phosphite [Tetrahedron Letters No. 49, pp. 5047-5050 (1972)]. Another equivalent of the acid chloride is a corresponding azolide, i.e., an amide of the corresponding acid whose amide nitrogen is a member of a quasiaromatic five membered ring containing at least two nitrogen atoms, i.e., imidazole. pyrazole, the triazoles, benzimidazole, benzotriazole and their substituted derivatives. As an example of the general method for the preparation of an azolide, N,N'- carbonyldiimidazole is reacted with a carboxylic acid in equimolar proportions at room temperature in tetrahydrofuran, chloroform, dimethylformamide or a similar inert solvent to form the carboxylic acid imidazolide in practically quantitative yield with liberation of carbon dioxide and one mole of imidazole. Dicarboxylic acids yield dimidazolide. The by-product, imidazole, precipitates and may be separated and the imidazolide isolated, but this is not essential. The methods for carrying out these reactions to produce a cephalosporin and the methods used to isolate the cephalosporin so produced are well known in the art.

Mention was made above of the use of enzymes to couple the free acid with compound ll. Included in the scope of such processes are the use of an ester, e.g. the methyl ester, of that free acid with enzymes provided by various microorganisms, e.g. those described by T. Takahashi et al., J. Amer. Chem. Soc, 94( l l 4035-4037 1972) and by T. Nara et al., J. Antibiotics (Japan) 24(5), 321-323 (1971) and in US. Pat. No. 3,682,777.

For the coupling of the substituted or unsubstituted D-mandelic acid (with or without a protecting group on the a-hydroxyl) as described above with compound 11 (or a salt or preferably an easily hydrolyzed ester or Schiff base, as with benzaldehyde, thereof) it is also convenient and efficient to utilize as the coupling agent N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) as described in J. Amer. Chem. Soc, 90, 823-824 and 1652-1653 (1968) and US. Pat. No. 3,455,929. The reaction is preferably carried out at 3035C. In benzene, ethanol or tetrahydrofuran using about equimolar quantities of all three reagents followed by conventional isolation and removal by conventional methods of any blocking groups present.

An additional process of the present invention comprises the preparation of the compounds of the present invention by the displacement of the 3-acetoxy group of a substituted or unsubstituted D-mandelamido-cephalosporanic acid (in which the a-hydroxy group is protected or unprotected and so is the carboxyl group) with 3-hydroxy-6-mercaptopyridazine and then removing the protecting group if any is present on the a-hydroxy group or on the carboxyl group or both. The displacement of such an acetoxy group with such a thiol is a well-known reaction and may be accomplished in solution as in water or aqueous acetone at a temperature of at least room temperature and preferably within the range of about 50 to 100C. in the presence of a mild base such as sodium bicarbonate, e.g. preferably near neutrality such as at about pH 6. An excess of the thiol is preferably employed. The reaction product is isolated by careful acidification of the reaction mixture followed by extraction with a water-immiscible organic solvent. Such substituted or unsubstituted D-mandelamido-cephalosporanic acids are prepared by the procedures described generally or specifically in J. Med. Chem. 17(1), 34-41 1974) and the references cited therein.

In the treatment of bacterial infections in man, the compounds of this invention are administered parenterally, in accordance with conventional procedures for antibiotic administration. in an amount of from about 5 to 200 mg./kg.lday and preferably about 5 to 20 mg./kg./day in divided dosage, e.g. 3 to 4 times a day. They are administered in dosage units containing, for example, 125, 250 or 500 mg. of active ingredient with suitably physiologically acceptable carriers or excipients. The dosage units are preferably in the form of liquid preparations such as solutions or suspensions.

START] NG MATERIALS 3-Chloro-6-hydroxypyridazine A mixture of 22.47 g. (0.15 mole) of 3,6- dichloropyridazine and 50 ml. of acetic acid was refluxed for two hours. The reaction mixture was cooled and diluted with 50 ml. of water and then concentrated to dryness under reduced pressure. The residue was crystallized from water to give 15.8 g. of 3-chloro-6-hydroxypyridazine as colorless prisms which melted at 133-7C. (lit. l38140C.) See. N. Takabayashi, Yakugaku Zasshi, 75, 778 1955).

3-Hydroxy-o-mercaptopyridazine A mixture of 2.6 g. (0.02 mole) of 3-chloro-6- hydroxypyridazine and 5.0 g. (0.07 mole) of freshly prepared potassium hydrogen sulfide in 30 ml. of ethanol was heated at -140C. in a sealed tube for 6 hours. The reaction mixture was cooled and diluted with 200 ml. of water. Almost all organic solvent was removed by distillation under reduced pressure. The residual aqueous solution was acidified with dilute hydrochloric acid to pH 3 and extracted with ethyl acetate (6 X 50 ml.). The combined extracts were evaporated to dryness and the residue was reprecipitated from 30 ml. ofethanolligroin 1:1) to give 2.2 g. (87%) of amorphous 3-hydroxy-6-mercaptopyridazine. m.p. 158-159C. (lit. 157-158C.).

See .1. Druey et a1., Helv. Chem. Acta. 37, I21 1954).

3-Hydroxy-6-mercaptopyridazine To a solution of 5.6 g. (0.05 mole) of 3,6- dihydroxypyridazine in ml. of pyridine was added portion-wise 2.70 g. (0.012 mole) of phosphorus pentasulfide with vigorous stirring under refluxing. The refluxing was continued for 1 hour and then the reaction mixture was diluted with 200 ml. of water and concentrated to remove the pyridine. The resulting oily residue was suspended in water and extracted with ethyl acetate. The organic extracts were combined and concentrated again to give oily material which was triturated with a small amount of water to give 3-hydroxy-6- mercaptopyridazine as a yellow solid. Recrystallization from water afforded 0.62 g. (12%) of the product which was identical with that prepared above.

3 ,6- Dihydrox ypyridazine To a boiling solution of 315 g. (3 moles) of hydrazine dihydrochloride in 2 L of water was added portionwise 295 g. (3 moles) of finely ground maleic anhydride with stirring. After the addition was completed the heating was continued for 4 hours and then allowed to stand overnight in a refrigerator to give 285 g. (85%) of 3,6-dihydroxypyridazine as massive pillars. M.p. 290C.

3 ,6-Dichloropyridazine A mixture of 150 g. (1.33 moles) of 3,6- dihydroxypyridazine and 250 g. of phosphorus oxychloride was refluxed for 3 hours under protection from moisture. The excess of phosphorus oxychloride was removed under reduced pressure and the dark residue was pouted into 1 Kg. of crushed ice. The resulting precipitate was collected by filtration. The second crop of the product was obtained from the mother liquor by extraction with five 300 ml. portions of chloroform followed by treating with l g. of charcoal and evaporating the solvent. The first and second crops were combined, dissolved in 500 ml. of chloroform and treated again with one g. of charcoal and concentrated to give 165 g. (83%) of 3,6-dichloropyridazine as fine needles melting at 60-61C. (in a sealed tube).

6-Chloro-3-hydroxypyridazine A suspension of 60 g. (0.4 mole) of 3,6- dichloropyridazine in 200 ml. of hydrochloric acid was refluxed for 2 hours until a clear solution was obtained. The clear solution was treated with ca. 1.5 g. of active carbon and filtered. The filtrate was concentrated under reduced pressure to give 6-ch1oro-3- hydroxypyridazine as colorless needles. Yield 49.5 g.

(98%) M.p. l37-139C.

3-Hydroxy-6-mercaptopyridazine A mixture of 50 g. (0.38 mole) of 6-chloro-3- hydroxypyridazine, 60 g. (0.83 mole) of potassium hydrogen sulfide in 250 ml. of ethanol was heated in a 500 ml. autoclave at 140C. for 14 hours with magnetic stirring. The pressure reached to -20 Kg./cm The mixture was evaporated to dryness and the residue was dissolved in 300 ml. of water. The aqueous solution was acidified with dil. hydrochloric acid to pH 3 and extracted with ten 200 ml. portions of ethyl acetate. The combined extracts were concentrated to give 34.3 g. (70%) of amorphous 3-hydr0xy-6-mercaptopyridazine. M.p. 151152C.

7-Amino-3-( 6-hydroxypyridazin-3-ylthiomethyl )-3- cephem-4-carboxylic acid (3 A mixture of 0.60 g. (0.0047 mole) of 3-hydroxy-6 mercaptopyridazine, 1.27 g. (0.0047 mole) of 7-aminocephalosporanic acid, 0.78 g. (0.0094 mole) of sodium bicarbonate in 25 ml. of 0.1 M phosphate buffer (pH 6.4) was heated at 60C. for 5 hours. The reaction mixture was filtered to remove a trace of insoluble material and the filtrate was adjusted to pH 5 with acetic acid to give brown precipitates which were collected by filtration, washed with water and acetone successively and dried in vacuo to give 7-amino-3-(6- hydroxypyridazin-3-ylthiomethyl)-3-cephem-4- carboxylic acid; 1.03 g. (71% M.p. 290300C. (decomp.)

IR: v 1805, 1680, 1650, 1580, 1415 cm".

UV: A 249 nm (19400).

(1H. d, 14 Hz), 3.65 (1H, d. 14 Hz), 3.72 (1H. d, 19 Hz), 4.90 (1H, d, 4 Hz), 5.30 (1H, d, 4 Hz), 6.75 (1H, d, 10 Hz), 7.30 (1H, d, 10 Hz).

Anal Calcd. for C H, N.,O S .l/2 H O: C, 41.25; H, 3.75; N, 16.04; S, 18.36. Found: C, 41.45; H, 3.70; N, 15.83; S, 18.03.

7-Amino- 3-( 3-hydroxypyridazin- 6-ylthiomethyl )3- cephem-4-carboxylic acid (3) A mixture of 141 g. (0.52 moles) of 7-ACA, 92 g. (1.1 moles) of sodium bicarbonate and 73 g. (0.57 moles) of 3-hydroxy-6-mercaptopyridazine in 1.5 L of 0.1 M phosphate buffer (pH 6.4) was heated at 6065C. under nitrogen atmosphere for 4 hours. The hot mixture was treated with 2 g. of charcoal and filtered. The filtrate was cooled to room temperature and adjusted to pH 4.5 with glacial acetic acid to give the precipitate, which was collected by filtration, washed with one L of acetone and air dried at room temperature to yield 125 g. of 7-amino-3-(3- hydroxypyridazin -6-y1thiomethyl)-3-cephem-4- carboxylic acid. M.p. 240250C. (dec.).

Pivaloyloxymethyl 7-Amino-3-( 6-hydroxypyridazin-3 -ylthiomethyl )-3- cephem-4-carboxylate.

Method A The title compound is produced by substituting for the 7-aminocephalosporanic acid used immediately above an equimolar weight of pivaloyloxymethyl 7-aminocephalosporanate hydrochloride prepared according to Example 2 of U.K. Pat. No. 1,229,453 from 7-aminocepha1osporanic acid. German Pat. No. 1,904,585 (Farmdoc 39,445) is equivalent to U.K. Pat. No. 1,229,453.

Method B The title compound is produced by substituting for the 0.025 mole (6.8 g.) 7-aminocephalosporanic acid used in the procedure of Example 2 of U.K. Pat. No. 1,229,453 an equimolar weight of 7- amino- 3-( o-hydroxypyridazin- 3-ylthiomethyl )-3- cephem-4-carboxylic acid.

The respective acetoxymethyl, methoxymethyl, acetonyl and phenacyl esters of 7-amino-3-( 6- hydroxypyridazin-3-ylthiomethyl)-3-cephem-4- carboxylic acid are prepared by substituting in Method B above for the chloromethyl pivalate used therein an equimolar weight of chloromethyl acetate, chloromethyl methyl ether, chloroacetone and phenacyl bromide, respectively.

The preferred esters of the cephalosporins of the present invention are the pivaloyloxymethyl, acetoxymethyl, methoxymethyl, acetonyl and phenacyl esters. All are useful intermediates in the production of the cephalosporin having a free carboxyl group and the first three are also of interest because on oral administration they provide different rates and amounts of absorption and give differing concentrations of the active antibacterial agent in blood and tissues.

These five esters of 7-aminocephalosporanic acid are each prepared by known methods. One excellent procedure is that of US. Pat. No. 3,284,451 in which sodium cephalothin is esterified by reaction with the corresponding active chloro or bromo compound (e.g. phenacyl bromide, chloroacetone, chloromethyl ether, pivaloyloxymethyl chloride [also called chloromethyl pivalate], acetoxymethyl chloride) and then the thienylacetic acid sidechain is removed enzymatically as in the same patent or chemically as in US. Pat. No. 3,575,970 and in Journal of Antibiotics, XXXV (11), 767-773 1971 In another good method the triethylamine salt of 7-aminocephalosporanic acid is reacted directly with the active halogen compound, as in UK. Pat. No. 1,229,453.

These esters of 7-aminocephalosporanic acid are then reacted with the nucleophile 3-hydroxy-6- mercaptopyridazine (which can also be named 6- hydroxy-3-mercaptopyridazine or o-hydroxypyridazin -3-thiol) in the same manner as is illustrated herein for 7-aminocephalosporanic acid itself. The '3thiolated ester of 7-aminocephalosporanic acid is then coupled with the substituted or unsubstituted D-mandelic acid. Before or after removal of any blocking group on the a-hydroxy group of the 7-sidechain, the ester of the cephalosporin so obtained is, if not used per se, converted to its free acid. including if desired, any salt by removal of the esterifying group, as by aqueous or enzymatic hydrolysis (as with human or animal serum) or acidic or alkaline hydrolysis or by treatment with sodium thiophenoxide as taught in US. Pat. No. 3,284,45l and, in the penicillin series, by Sheehan et aL, J. Org. Chem. 29(7), 2006-2008 (I964).

In another alternative synthesis, the 3-thiolated 7-aminocephalosporanic acid is prepared as described herein and then acylated at the 7-amino group and finally esterified, as by reaction of the appropriate alcohol with the acid chloride prepared, for example, by reaction of the final cephalosporin with thionylchloride or by other essentially acidic esterification procedures.

Preparation of D-mandelic acid carboxyanhydride COCI: H ("H (OOH D-Mandelic acid carboxyanhydride (2) Phosgene was bubbled through a solution of 2.0 g. (0.0] 3 mole) of D(-)-mandelic acid l in dry tetrahydrofuran for 30 minutes. The solution was allowed to stand overnight after which time it was heated under reflux to It) minutes. Evaporation of the solvent under reduced pressure afforded an oily residue which was solidified by trituration with n-hexane (20 ml.). The product was collected by filtration and dried in vacuo on KOH. Yield 2.3 g. of D-mandelic acid carboxyanhydride.

IR: u,,,,,,"" I895, I875, I780 cm.

The preferred and most active compounds of the present invention are those having the D configuration at the a-carbon atom in the 7-side-chain, that is, those made from D-mandelic acid or a monosubstituted D- mandehic acid as illustrated herein. In addition, the configuration at the two optically active, asymmetric centers in the 62-lactam nucleus is that found in cepha- Iosporin C produced by fermentation and in the laminocephalosporanic acid derived therefrom.

The following examples are given in illustration of, but not in limitation of, the present invention. All temperatures are in degrees Centigrade. 7-Aminocephalosporanic acid is abbreviated as 7-ACA; -ACArepresents the moiety having the structure door-r and thus 7-ACA can be represented as Methyl isobutyl ketone is represented as MIBK. Skellysolve B" is a petroleum ether fraction of HP. 68 C. consisting essentially of n-hexane.

DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLE 1 88-8283; 7-[ Da-Hydroxy-a-phenylacetamido]-3-( 6 hydroxypyridazin-3-ylthiomethyl )-3-cephem-4- carboxylic acid (4) D-()-Mandelic acid carboxyanhydride (2) (l.l g., 6 mmoles) was added portionwise to a stirred solution of 7-amino-3-(6-hydroxypyridazin-3ylthiomethyl)-3- cephem-4-carboxylic acid (3) (L02 g., 3 mmoles) and NaHCO (0.84 g., 10 mmoles) in 50% aqueous acetone (50 ml.) at 0 to 5 C. The reaction mixture was stirred at room temperature for one hour and washed with ether (50 ml.). The aqueous layer was acidified to pH 2 with dil. HCI to precipitate a gummy substance which was collected, washed with water [0 ml.) an dissolved in tetrahydrofuran (THF, 50 ml.). The solution was treated with carbon and filtered. The filtrate was evaporated under vacuum below 40 C. to afford an oily residue which was solidified by trituration with ether (50 ml.), collected by filtration and washed with ether (20 ml.) to give 0.64 g. (47%) of 7-[D-a-hydroxy-aphenylacetamido ]-3-( 6-hydroxypyridazin-3- ylthiomethyl)-3-cephem-4-carboxylic acid (4). M.p. l45-l52 C. (dec.)

IR: v I780, I720, I670, I580 cm.

EXAMPLE 2 6-[ D-a-Hydroxy-a-phenylacetamido1-3-(6-hydroxypyridazin-3-ylthiomethyl)-3-cephem-4-carboxylic acid (4 (lot 2) A solution of D-(-)-mandelic acid carboxyanhydride (2) (4.5 g., 25 mmoles) in anhydrous acetone (50 ml.)

was added dropwise to a solution of 7-amino-3-(6- hydroxypyridazin-3-ylthiomethyl )-3-cephem-4- carboxylic acid (3) (5.0 g., 14.7 mmoles) and NaHCQ'; (4.2 g., 50 mmoles) in 50% aqueous acetone (200 ml.) with stirring at 5 C. After the addition was completed the stirring was continued for 1 hr. at ambient temperature. The reaction mixture was extracted with ether (3 X 50 ml.) and the aqueous layer was acidified to pH 2 with dil. HCl. The resulting precipitate was dissolved in THF (200 ml.) and treated with active carbon (1 g.). The solution was evaporated under reduced pressure (30 mm. Hg.) below 40 C. The residue was triturated with ether (200 ml.) to give 2.67 g. of the crude 4. The crude 4 (2.30 g.) was dissolved in hot THF (40 ml.) and treated with active carbon (0.5 g.). The solution was diluted with ether (300 ml.) and the resulting precipitate was collected and washed well with ether (100 ml.) Yield 1.60 g. of 6-[D-a-hydroxya-phenylacetamido1- 3-( 6-hydroxypyridazin- 3- ylthiomethyl)-3-cephem-4-carboxylic acid (4) (lot 2) having m.p. 160l70 C. (dec.).

1R: v,,,,,,"" 1780, 1720, 1670, 1580 cm.

NMR: 5,,,,,,""" 3.55 (2H, br-s, 2-CH 3.89 (1H,

d, Hz, C'H S), 4.17 (1H, d, 15 Hz, CH- -S), 5.00 (1H, d, 4 Hz, 6-H), 5.04 (1H, s, -CH-O), 5.60 (1H, d-d, 4 and 9 Hz, 7-H), 6.70 (1H, d, 10 Hz. pyridazin-H), 7.17.4 (6H, m, phenyl-H and pyridazin-H), 8.6(1H, d, 9 Hz, CONH Anal. Calcd. for C- H,,,N O S C, 50.62; H, 3.82; N,

11.81; S, 13.51.F0und: C,50.67, 50.39; H, 3.96, 4.27; N, 10.69, 10.97; S, 12.85.

EXAMPLE 3 Sodium 6-[ D-a-hydroxy-ahydroxy-a-phenylacetamido 3-( 6- hydroxypyridazin-3-ylthiomethyl )-3-cephem-4- carboxylate (lot 3) To a solution of 4 (1.0 g., 2.1 mmoles) in ml. of THF was added 2.2 m1. of sodium 2-ethy1hexanoate (1M, ethyl acetate solution) under stirring at room temperature. The solution was diluted with ethyl acetate 100 ml) to afford a precipitate, which was washed well with ethyl acetate to give 1.05 g. of sodium 6-[D- a-hydroxy-a-phenylacetamido]-3-(6- hydroxypyridazin-3-ylthiomethyl )-3-cephem-4- carboxylate. M.p. 260 -270 C. (dec.).

IR: v,,, ,""3600-2800, 1760, 1660, 1560, 1580,

UV: mmr nm lrm s NMR: 8,,,,,,,":" 3.15 (1H, d, 18 Hz, 2-H), 3.64 (1H, d, 18 Hz, 2-H), 3.70 (1H, d, 13 Hz, 3-CH,), 4.40 (1H, d, 13 Hz, 3-CH 4.90 (1H, d, 4 Hz, 6-H), 5.19 (1H, s, CH-O), 5.50 (1H, d, 4 Hz, 7-H), 6.80 (1H, d. 10 Hz, pyridazin-H), 7.7-7.4 (6H, m, benzen-H and pyridazin-H).

Anal. Calcd. for C ,,H, N.,O.,S Na.H O: C, 46.84; H, 3.72; N, 10.89; 5, 12.46. Found: C, 47.00. 46.90; H, 3.55, 3.62; N, 10.43, 10.31; S, 12.05, 11.96.

In vitro Antibacterial Activity of BB-S283 lot 2 and 3 by Tube Dilution Method (Nutrient Broth).

MIC (meg/mg.) B85283 BB-SZBI Organisms (lot 2) (lot 3) S. nun-us Smith 0.025 0.05

uurem' Smith 0.1 0.2 50% serum 5. uurem BX-1633 0.4 0.8 .S'. aureus Al5097 10 dil. 100 St. pyugenes A9604 0.02 0,04 Dip. pneumrmiue A9585 0.08 0.04 Elmrhucter t'luucue A9656 100 50 cvli NIH] 0.4 0.4 E. culiJuhl A1511) 3.1 6.3 E. t'uli A9675 3.] 3.1 Kl. pneumoniue A9977 0.8 1.6 KI. pncumuniae A15130 1.6 3.1 Pr. mirabiiis A9900 3.1 1.6 Pr. morgzmii A15l53 l0 dil. 0.4 0.4 Sal. vmeritidis A9531 0.2 0.4 Ser. nlarcescens A2001) l0" dil. 50 100 Rs. ueruginm'a A9843 l0" dil. 100 100 EXAMPLE 4 Substitution of the D-mande1ic acid carhoxyanhydride in the procedure of Example 1 of an equimolar weight of the carboxyanhydrides prepared in similar fashion from the monosubstituted D-mandelic acids D-2-ch1oro-mandelic acid,

D-3-chloro-mande1ic acid,

D-4-chloro-mandelic acid,

D-Z-bromo-mandelic acid,

D-3-bromo-mande1ic acid,

D-4-bromo-mandelic acid,

D-Z-fluoro-mandelic acid,

D-3-fluoro-mandelic acid,

D-4-fluoro-mandelic acid,

D-2-trifluoromethyl-mandelic acid,

D-3-trifluoromethyl-mandelic acid,

D-4-trifluoromethyl-mandelic acid,

D-2-amino-mandelic acid,

D-3amino-mande1ic acid,

D-4-amino-mandelic acid,

D-2-nitro-mandelic acid,

D-3-nitro-mandelic acid,

D-4-nitro-mandelic acid,

D-Z-hydroxy-mandelic acid,

D-3-hydroxy-mandelic acid,

D-4-hydroxy-mandelic acid,

D-Z-methyl-mandelic acid,

D-3-methy1-mande1ic acid,

D-4-methyl-mandelic acid,

D-Z-methoxy-mandelic acid,

D-3-methoxy-mande1ic acid, and

D-4-methoxy-mandelic acid respectively produces 7-( D-2-ch1oro-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-3-chloro-mande1amido )-3-( 6- hydroxypyridazine-3-y1thiomethyl )-3-cephem-4- carboxylic acid,

7-( D-4-chloro-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-2-bromo-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-3-bromo-mandelamido)-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-4-bromo-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-Z-fluoro-mandelamido)-3-(6- hydroxypyridazine-3-ylthiomethyl)-3-cephem-4- carboxylic acid,

7-(D-3-fluoro-mandelamido)-3-(6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-4-fluoro-mandelamido)-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-Z-trifluoromethyl-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-3-trifluoromethyl-mandelamido )-3-( 6- hydrogtypyridazine-3-ylthiomethyl)-3-cephem-4- carboxylic acid.

7-( D-4-trifluoromethyl-mandelamido)-3-(6- hydroxypyridazine-3-ylthiomethyl )-3-cephen1-4- carboxylic acid.

7-( D-Z-amino-mandelamido)-3(6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid.

7-( D-3-amino-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carhoxylic acid,

7-( D-4-amino-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid,

7-( D-Z-nitro-mandelamido)-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid.

7-( D-3-nitro-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl)-3-cephem-4- carboxylic acid.

7-( D-4-nitro-mandelamido)-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carhoxylic acid.

7-( D-2-hydroxy-mandelamido)-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4 carhoxylic acid.

7-( D-3-hydroxy-mandelamido)-3-(6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid.

7-( D-4-hydroxy-mandelamido)-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid.

7-( D-Z-methyl-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl)-3-cephem-4- carboxylic acid.

7-( D-3-methyl-mandelamido)-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid.

7-( D-4-methyl-mandelamido )-3-( 6- h yd roxypyridazine-3-ylthiomethyl J-3-cephem-4- carboxylic acid.

7-( D-Z-methoxy-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid.

7-( D-3-methoxy-mandelamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl J-3-Cephem-4- carboxylic acid and 7-( D-4-methoxy-mandelamido 3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid respectively.

EXAMPLE 5 Substitution for the D-mandelic acid carboxyanhydride in the procedure of Example I of an equimolar weight of the carboxyanhydride prepared in similar fashion from D-Z-thiopheneglycolic acid and D-3-thi0- pheneglycolic acid respectively produces 7-(D-0zhydroxy-2-thienylacetamido)-3-(6-hyclroxypyridazine- 3-ylthiomethyl)-3-cephem-4-carboxylic acid and 7-( D- oz-hydroxy-S-thienylacetamido )-3-( 6- hydroxypyridazine-3-ylthiomethyl )-3-cephem-4- carboxylic acid respectively.

EXAMPLE 6 7-( D-oz-Hydroxy-a-phenylacetamido )-3 6- hydroxypyridazin-I i-ylthiomethyl )-3 -cephem-4- carboxylic acid prepared from 7-D-mandelamidocephalosporanic acid.

0.27 Mole of sodium 7-D-mandelamidocephalosporanate is suspended in l000 ml. of 0.1 M phosphate buffer of pH 6.4 and there is added 0.3l moles of 3- hydroxy-6-mercaptopyridazine. The solution is heated at 55 C. under a nitrogen atmosphere for 5 hours. After 1 hour the pH is adjusted to 6.4 by addition of a .mall amount of 40% H -,PO At the end of the 5 hour heating period the solution is cooled to 23 C. and the pH adjusted to 2 by the addition of 3 N HCl under a layer of ethyl acetate. The product is extracted into ethyl acetate and stirred for IS min. at 23 C. with 2 g. of (Darco KB) decolorizing charcoal. The mixture is then filtered through a pad of diatomaceous earth (Celite") and the ethyl acetate removed from the til-- trate under vacuum. The residue is triturated to a solid with diethyl ether, collected by filtration and dried over P 0 under vacuum to yield solid 7-(D-oz-hydroxy-oephenylacetamido )-3-( 6-hydroxypyridazin-3- ylthiomethyl )-3-cephem-4-carboxylic acid.

We claim:

I. An acid having the D configuration in the 7- sidechain and the formula wherein R is 6. An acetoxymethyl ester of an acid of claim l.

7. An acetonyl ester of an acid of claim 1.

8. A phenacyl ester of an acid of claim 1.

9. A methoxymethyl ester of an acid of claim 1.

l0. An acid of claim 1 having the D configuration in the 7-sidechain and the formula wherein Y is hydrogen, chlorine, bromine, fluorine, trifluoromethyl, amino, nitro, hydroxy, lower alkyl of 1-4 carbon atoms or lower alkoxy of 14 carbon atoms.

ii. The sodium salt of an acid of claim l0.

12. The potassium salt of an acid of claim l0.

13. A nontoxic, pharmaceutically acceptable salt of an acid of claim l0.

l4. A pivaloyloxymethyl ester of an acid of claim l0.

[5. An acetoxymethyl ester of an acid of claim l0.

l6. An acetonyl ester of an acid of claim l0.

[7. A phenacyl ester of an acid of claim l0.

18. A methoxymethyl ester of an acid of claim 10.

19. The acid of claim I having the D configuration in the 7-sidechain and the formula 20. The sodium salt of the acid of claim 19.

2|. The potassium salt of the acid of claim 19.

22. A nontoxic, pharmaceutically acceptable salt of the acid of claim 19.

23. The pivaloyloxymethyl ester of an acid of claim 19.

24. The acetoxymethyl ester of an acid of claim 19.

25. The acetonyl ester of an acid of claim 19.

26. The phenacyl ester of an acid of claim 19.

27. The methoxymethyl ester of an acid of claim 19.

28. The acid having the D configuration in the 7- sidechain and the formula 29. The sodium salt of the acid of claim 28.

30. The potassium salt of the acid of claim 28.

31. A nontoxic, pharmaceutically acceptable salt of the acid of claim 28.

32. The pivaloyloxymethyl ester of an acid of claim 28.

33. The acetoxymethyl ester of an acid of claim 28.

34. The acetonyl ester of an acid of claim 28.

35. The phenacyl ester of an acid of claim 28.

36. The methoxymethyl ester of an acid of claim 28.

37. An acid of claim 1 having the D configuration in the 7-sidechz1in and the formula lOOH wherein R is chlorophenyl, bromophenyl, trifluoromethylphenyl, tolyl or methoxyphenyl.

38. The sodium salt of an acid of claim 37.

39. The potassium salt of an acid of claim 37.

40. A nontoxic, pharmaceutically acceptable salt of an acid of claim 37.

41. A pivaloyloxymethyl ester of an acid of claim 37.

42. An acetoxymethyl ester of an acid of claim 37.

43. An acetonyl ester of an acid of claim 37.

44. A phenacyl ester of an acid of claim 37.

45. A methoxymethyl esterof an acid of claim 37.

46. The acid having the D configuration in the 7- sidechain and the formula @ir gaf 54. The methoxymethyl ester of an acid of claim 46.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 910,900 Dated October 7, 1975 n Takav'uki Naito; Jun Okumura; Hajime Kamachi It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the claims, Claim 10 should read as follows:

10. An acid of claim 1 having the D configuration in the 7-sidechain and the formula Y OH -N /C-CH -s COOH wherein Y is hydrogen, chlorine, bromine, fluorine, trifluoromethyl, amino, nitro, hydroxy, lower alkyl of 1- carbon atoms or lower alkoxy of 1-H carbon atoms.

Signed and Scaled this third Day Of February 1976 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer (ummissiuner ufParenrs and Trademarks 

1. AN ACID HAVING THE D CONFIGURATION IN THE 7-SIDECHAIN AND THE FORMULA
 2. The sodium salt of an acid of claim
 1. 3. The potassium salt of an acid of claim
 1. 4. A nontoxic, pharmaceutically acceptable salt of an acid of claim
 1. 5. A pivaloyloxymethyl ester of an acid of claim
 1. 6. An acetoxymethyl ester of an acid of claim
 1. 7. An acetonyl ester of an acid of claim
 1. 8. A phenacyl ester of an acid of claim
 1. 9. A methoxymethyl ester of an acid of claim
 1. 10. An acid of claim 1 having the D configuration in the 7-sidechain and the formula
 11. The sodium salt of an acid of claim
 10. 12. The potassium salt of an acid of claim
 10. 13. A nontoxic, pharmaceutically acceptable salt of an acid of claim
 10. 14. A pivaloyloxymethyl ester of an acid of claim
 10. 15. An acetoxymethyl ester of an acid of claim
 10. 16. An acetonyl ester of an acid of claim
 10. 17. A phenacyl ester of an acid of claim
 10. 18. A methoxymethyl ester of an acid of claim
 10. 19. The acid of claim 1 having the D configuration in the 7-sidechain and the formula
 20. The sodium salt of the acid of claim
 19. 21. The potassium salt of the acid of claim
 19. 22. A nontoxic, pharmaceutically acceptable salt of the acid of claim
 19. 23. The pivaloyloxymethyl ester of an acid of claim
 19. 24. The acetoxymethyl ester of an acid of claim
 19. 25. The acetonyl ester of an acid of claim
 19. 26. The phenacyl ester of an acid of claim
 19. 27. The methoxymethyl ester of an acid of claim
 19. 28. The acid having the D configuration in the 7-sidechain and the formula
 29. The sodium salt of the acid of claim
 28. 30. The potassium salt of the acid of claim
 28. 31. A nontoxic, pharmaceutically acceptable salt of the acid of claim
 28. 32. The pivaloyloxymethyl ester of an acid of claim
 28. 33. The acetoxymethyl ester of an acid of claim
 28. 34. The acetonyl ester of an acid of claim
 28. 35. The phenacyl ester of an acid of claim
 28. 36. The methoxymethyl ester of an acid of claim
 28. 37. An acid of claim 1 having the D configuration in the 7-sidechain and the formula
 38. The sodium salt of an acid of claim
 37. 39. The potassium salt of an acid of claim
 37. 40. A nontoxic, pharmaceutically acceptable salt of an acid of claim
 37. 41. A pivaloyloxymethyl ester of an acid of claim
 37. 42. An acetoxymethyl ester of an acid of claim
 37. 43. An acetonyl ester of an acid of claim
 37. 44. A phenacyl ester of an acid of claim
 37. 45. A methoxymethyl esterof an acid of claim
 37. 46. The acid having the D configuration in the 7-sidechain and the formula
 47. The sodium salt of the acid of claim
 46. 48. The potassium salt of the acid of claim
 46. 49. A non-toxic, pharmaceutically acceptable salt of the acid of claim
 46. 50. The pivaloyloxymethyl ester of an acid of claim
 46. 51. The acetoxymethyl ester of an acid of claim
 46. 52. The acetonyl ester of an acid of claim
 46. 53. The phenacyl ester of an acid of claim
 46. 54. The methoxymethyl ester of an acid of claim
 46. 